Pereiro delivered a flurry of punches in the first round, promoting Vargas to shake his head dismissively. The Argentine stuck out his tongue and clowned as Vargas complained of shots to the back of the head. Pereiro got a warning early in the second for the illegal blows.

Vargas floored Pereiro with a right hand in the second round. The Argentine rallied in the third, catching Vargas at the ropes but the local fighter weathered the storm and came back strongly.

A string of body shots late in the sixth took a toll on Pereiro.

Vargas (30-4-2) was coming off a decision loss to former world champion Amir Khan at welterweight in a September fight in Birmingham, England, that saw both fighters hit the canvas.

The Colombian-born Vargas is looking to move down in weight while Pereiro (27-1-0), who has fought mostly at lightweight (135 pounds), moved up for the fight. The two were supposed to fight at a catchweight of 144 pounds — as Vargas prepares a move to light-welterweight (140 pounds) — but both were introduced at 151 pounds.

Fighters weigh in twice in Ontario. Vargas met his 144-pound target at the first weigh in.

Vargas has done most of his fighting at welterweight (147 pounds) and super-welterweight (154). He says he tries to keep his weight under 160 when not fighting.

Vargas tried fighting at a lower weight with mixed results in a June draw with Argentina's Mauro Maximiliano Godoy. Since then he has started working with nutritionist Greg Marriott.

The 40-year-old Sengalese-born Colliander was a late replacement on the card and he made the most of it, rapping into a microphone en route to the ring.

At 267 pounds, Colliander (15-3-0) was a load but the veteran Swede was enough of a threat to keep the chiselled Prenga (9-1-0) from rushing in. And when Prenga threatened, Colliander attached himself to the Canadian like a refrigerator-sized limpet.

A frustrated Prenga, who was cut high on the head in the fourth round, finally connected in the sixth. Colliander went down and he and his corner decided they had had enough, prompting a stoppage at 2:16.

NABA and NABO middleweight champion Patrice Volny of Montreal won a majority 10-round decision (95-95, 97-93, 98-92) over challenger Ryan Young of Oakville, Ont. Young (12-4-0) kept coming forward but Volny (13-0-0) had good defence and a deeper arsenal.

Pan Am Games boxing champion Arthur (The Chechen Wolf) Biyarslanov won his pro debut in short order, stopping Mexican welterweight Ernesto Cardona Sanchez at 2:34 of the first round.

After briefly taking the measure of his opponent, the Montreal-based Biyarslanov found his range and eventually knocked the Mexican down in the corner with a left to the liver and then a right to the head. Wanting no more, Sanchez (3-6-0) stayed down.

"I wasn't nervous. I've been waiting for this for so long," said Biyarslanov. "It's been 15 months since I last fought. I couldn't wait to get in the ring, to be honest. It felt great to be back."

Biyarslanov said he may drop down to fight at lightweight (135 pounds). He weighed 141 this time.

Biyarslanov, 85-13 as an amateur, defeated Cuba's Yasniel Toledo at the 2015 Pan Am Games in Toronto. The 23-year old southpaw was the only Canadian male boxer to qualify for the 2016 Rio Olympics.

Montreal welterweight Dierry (All In) Jean stopped Noe Nunez (18-7-2) at 2:33 of the first round. The Mexican hit the canvas near the ropes and, when he couldn't stay on his feet after getting up, referee Donovan Boucher intervened.

The 36-year-old Jean (31-2-1) has twice fought for world titles, losing to Terence Crawford in 2015 (for the WBO super-lightweight crown) and Lamont Peterson in 2014 (for the IBF super-lightweight championship).

Jean returned to action in September after a 28-month hiatus, stopping Abraham Gomez via TKO.

Returning to the ring after an 11-year absence, hard-hitting Halifax middleweight Moncef (Buddy) Askri won by TKO over Mexico's Jesus Javier Mendoza at 1:40 of the first round. The 37-year-old Askri improved to 11-0-0 while Mendoza slipped to 7-7-1.

Askri stepped away from the sport for a variety of reasons. He began to have hand problems, his lifestyle started to go south and then his father passed away.

He kept saying to himself he would get back training next month. Instead years passed.

In April, he weighed 205 pounds. But three months training twice a day sculpted his body to a lean 160 pounds.

Toronto light-heavyweight Nick Fantauzzi (7-0-0) won a majority decision over a game Marco Parente (1-4-2) of Woodbridge, Ont., in a crowd-pleasing six-round bout.